Rolling metals



' D. K. MILLER.

(No Model.)

ROLLING METALS.

No. 467,512. Patented Jan. 26, .1892.

Mm x Mw r Urvrrnn STATES PATENT OFFICE.

DANIEL K. MILLER, OF PHILADELPHIA, PENNSYLVANIA.

ROLLING METALS.

SPECIFICATION forming part of Letters Patent No. 467,512, dated January26, 1892.

Application filed March 28, 1889. Renewed December 1'7I 1890. Againrenewed June 25, 1891. Serial No. 397,433- (No model.)

To aZZ whom it may concern:

Be it known that I, DANIEL K. MILLER, a citizen of the United States,and a resident of Philadelphia, Pennsylvania, have invented certainImprovements in Rolling Metals, of which the following is aspecification.

Theobject of my invention is to attain practical accuracy and uniformityin the thickness of rolled bars, plates, sheets, or other forms ofrolled metal; and this object I atcam in the manner hereinafter setforth, reference being had to the accompanying drawings, in which-Figure 1 is'a longitudinal section of sufficient of a rolling-mill toillustrate the invention. Fig. 2 is an end view looking in the directionof the arrow 1,Fig. 1; and Fig.3 is an end view looking in the directionof the arrow 2, Fig. 1, but illustrating a modification in theconstruction of part of the mill.

It is well known that in rolling-mills as at present constructedaccuracy inthe rolling and absolute or even substantial uniformity inthickness in all parts of the bar, plate, sheet, or other form in whichthe metal is rolled cannot be attained, for as there is always avariation in the degree of hardness or density of the metal subjected tothe action of the rolls and, consequent variation in the degree ofresistance to compression offered by said metal, and as there is alwaysmore or less spring in even the heaviest roll housings or frames itfollows that the softer portions will be compressed to a greater extentthan the harder or denser portions, and thick and thin places in therolled metal must result, and although such inequalities in thicknessmay be extremely slight they are suflicient to entail considerableexpense in addition to that of rolling in order to bring the rolledmetal into condition for use for many purposes in which great acon racyis desired. If, however, the rolls of the mill are prevented fromseparating beyond a certain predetermined 1imit,or rather if suchseparation requires the exercise of more force than is required tocompress the metal which is being rolled, it follows that the metalcompressed between the rolls must necessarily be reduced to a thicknesscorresponding with such predeterminedlimit of separation of the rolls.

In the rolls shown in Figs. 1 and 2 of the drawings, A A represent theopposite housings, which are adapted for the reception of thebearing-boxes B B of the upper and lower rolls D D, each of the boxes inthe present instance being shown as a two-part box, although it mayconsist of a single box, if desired.

Between each pair of boxes is interposed a filling-piece or block F, ofmetal or other material, which offers to compression a resistancegreater than the maximum strain which is exerted upon the roll-boxes bythe housings.

In preparing the mill for operation the upper box is subjected by meansof tightening-screws a a to a downward pressure considerably in excessof that required to compress the metal which is to be rolled, theresultbeing that the housings are stretched or subjected to a straingreater than any strain to which they are likely to be subjected by' therolling operation. Hence there can be no stretch or spring of thehousings during the rolling operation and no separation of the rolls dueto the elasticity of the metal composing the housings, while theinterposed filling pieces or blocks F serve to permit of such stretchingor straining of the housings Without bringing any portions of the rollsinto contact and without exerting any undue pressure upon the journalsof the rolls, so that the rotation of the rolls when no rolling is beingdone does not require any more power than though the housings were notunder strain. The pass presented by the rolls under these circumstancesis substantially accurate and uniform at all times, as said rolls cannotbe separated beyond the predetermined limit by the strain of the metalpassing between them, nor can the rolls approach closer to each otherthan the distance regulated by the thickness of the interposed medium F.Hence it follows that metal originally thicker than the pass presentedby the rolls when fully separated must by the action of the mill bereduced throughout to a uniform thickness corresponding to the size ofsaid pass. There may, however, bea tendency of the rolls to spring inthe middle and thus produce rolled forms thicker in the center than atthe edges. If, however, the rolls have journals projecting beyond theICO bearings such springing of the rolls will have the efiect of causingsaid projecting portions of the roll-journals to approach each other,the bearings acting as fulcrums. This tendency is therefore corrected byinterposing between such projecting portions of the rolljournals fillingmediums, which, like those heretofore alluded to as being interposedbetween the boxes of the rolls, are of such character as to offergreater resistance to compression than the force exerted to bring therolls together. In Fig. 1 I have shown different forms of such fillings,and it will be evident that other forms may be used, if desired. At oneend of the mill rolls 1) are applied to the projecting ends of thejournals of the main rolls and meet at a point equidistant between theaxes of the rolls, while at the other side of the mill there are twoblocks d 01, one forming a bearing for the lower half of the journal ofthe upper roll and the other forming a bearing for the upper half of thejournal of the lower roll.

As the housings have been subjected to such strain as prevents anystretching of the same when the mill is at work and as the outer rollsor filling-pieces prevent any approach of the outer projecting portionsof the journals of the two rolls, these two causes 00- operate toeffectually preclude any deflection of the journal of either roll, suchas would be caused by the springing of the rolls in the center.

Instead of having the rolls or blocks meet at the central line, it ispreferable in most cases to use wedges or filling-pieces f, as shown,for instance, by dotted lines in Figs. 2 and 3, so that the thickness ofthe interposed medium may be varied, depending upon the size of the passto be formed between the rolls D D, and the filling-piece of the roll I)may be movable, being, for-instance, in the form of a ring, as shown,and like rings may, if desired, be inserted between the rolls D 1), orreplaceable or adjustable filling-pieces between the rolls band blocks01 may in some cases serve in lieu of the filling-pieces between theboxes.

In Fig. 3 I have shown, instead of the compressing-screws a for actingupon the upper boxes of the rolls, tension-screws a, passing through thehousings and having at the upper ends nuts (1 bearing upon the upperplate 9, which acts upon the box of the upper roll, these bolts a inthis case being subjected to tension by the nuts, so as to constitutethe resisting medium to prevent the undue separation of the rolls bystrain exerted thereupon during the rolling operation, and it will beevident that other means than bolts or screws say, for instance,wedge-plates, such as shown by dotted lines in Fig. 2may be used for thestretching or straining of the housings without subjecting the rolls tostrain, or both means maybe employed, the wedges for straining orstretching the body of the housing and the bolts or screws forassisting-the wedges and for straining that part of the housing abovethe wedges.

Having thus described my invention, I claim and desire to secure byLetters Patent-- 1. The mode herein described of securing uniformity inrolled forms of metal, said mode consisting in preventing separation ofthe rolls beyond a predetermined limit by subjecting the roll-housingsprior to the rolling operation to a strain in excess of the pressurerequired to effect the reduction of the metal without subjecting therolls to the strain, substantially as specified. 2. The mode hereindescribed of securing uniformity in each of a number of thicknesses ofrolled forms of metal, said mode consisting in subjecting the housingsof the rolls before the rolling operation to strain in excess of thepressure required for the reduction of the metal which is being rolled,restricting the approach of the rolls under the strain by a mediumpresenting a greater resistance to compression than the force exerted tobring the rolls together, and varying the thickness of said medium toaccord with the desired thickness of the rolled product, substantiallyas specified. 1 I

3. The mode herein described of securing uniformity in rolled forms ofmetal, said mode consisting in subjecting the housings of the rollsbefore the rolling operation to strain in excess of the pressurerequired for the reduction of the metal which is being rolled andpreventing springing of the rolls by interposing between their journalsbeyond the housings a medium offering greater resistance to compressionthan the metal which is being rolled, substantially as specified.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing'witnesses.

DANIEL K. MILLER. Witnesses:

WILLIAM D. CONNER, HARRY SMITH.

